1 /*
2  * Copyright (c) 1995, 2006, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package sun.awt.image;
27 
28 import java.io.InputStream;
29 import java.io.IOException;
30 import java.net.HttpURLConnection;
31 import java.net.URL;
32 import java.net.URLConnection;
33 import java.net.MalformedURLException;
34 import sun.net.util.URLUtil;
35 
36 public class URLImageSource extends InputStreamImageSource {
37     URL url;
38     URLConnection conn;
39     String actualHost;
40     int actualPort;
41 
URLImageSource(URL u)42     public URLImageSource(URL u) {
43         SecurityManager sm = System.getSecurityManager();
44         if (sm != null) {
45             try {
46                 java.security.Permission perm =
47                       URLUtil.getConnectPermission(u);
48                 if (perm != null) {
49                     sm.checkPermission(perm);
50                 }
51             } catch (java.io.IOException ioe) {
52                 sm.checkConnect(u.getHost(), u.getPort());
53             }
54         }
55         this.url = u;
56 
57     }
58 
URLImageSource(String href)59     public URLImageSource(String href) throws MalformedURLException {
60         this(new URL(null, href));
61     }
62 
URLImageSource(URL u, URLConnection uc)63     public URLImageSource(URL u, URLConnection uc) {
64         this(u);
65         conn = uc;
66     }
67 
URLImageSource(URLConnection uc)68     public URLImageSource(URLConnection uc) {
69         this(uc.getURL(), uc);
70     }
71 
checkSecurity(Object context, boolean quiet)72     final boolean checkSecurity(Object context, boolean quiet) {
73         // If actualHost is not null, then the host/port parameters that
74         // the image was actually fetched from were different than the
75         // host/port parameters the original URL specified for at least
76         // one of the download attempts.  The original URL security was
77         // checked when the applet got a handle to the image, so we only
78         // need to check for the real host/port.
79         if (actualHost != null) {
80             try {
81                 SecurityManager security = System.getSecurityManager();
82                 if (security != null) {
83                     security.checkConnect(actualHost, actualPort, context);
84                 }
85             } catch (SecurityException e) {
86                 if (!quiet) {
87                     throw e;
88                 }
89                 return false;
90             }
91         }
92         return true;
93     }
94 
getConnection()95     private synchronized URLConnection getConnection() throws IOException {
96         URLConnection c;
97         if (conn != null) {
98             c = conn;
99             conn = null;
100         } else {
101             c = url.openConnection();
102         }
103         return c;
104     }
105 
getDecoder()106     protected ImageDecoder getDecoder() {
107         InputStream is = null;
108         String type = null;
109         URLConnection c = null;
110         try {
111             c = getConnection();
112             is = c.getInputStream();
113             type = c.getContentType();
114             URL u = c.getURL();
115             if (u != url && (!u.getHost().equals(url.getHost()) ||
116                              u.getPort() != url.getPort()))
117             {
118                 // The image is allowed to come from either the host/port
119                 // listed in the original URL, or it can come from one other
120                 // host/port that the URL is redirected to.  More than that
121                 // and we give up and just throw a SecurityException.
122                 if (actualHost != null && (!actualHost.equals(u.getHost()) ||
123                                            actualPort != u.getPort()))
124                 {
125                     throw new SecurityException("image moved!");
126                 }
127                 actualHost = u.getHost();
128                 actualPort = u.getPort();
129             }
130         } catch (IOException e) {
131             if (is != null) {
132                 try {
133                     is.close();
134                 } catch (IOException e2) {
135                 }
136             } else if (c instanceof HttpURLConnection) {
137                 ((HttpURLConnection)c).disconnect();
138             }
139             return null;
140         }
141 
142         ImageDecoder id = decoderForType(is, type);
143         if (id == null) {
144             id = getDecoder(is);
145         }
146 
147         if (id == null) {
148             // probably, no appropriate decoder
149             if  (is != null) {
150                 try {
151                     is.close();
152                 } catch (IOException e) {
153                 }
154             } else if (c instanceof HttpURLConnection) {
155                 ((HttpURLConnection)c).disconnect();
156             }
157         }
158         return id;
159     }
160 }
161